SYNOPSYS: SYNthesis of OPtical SYStems

A lens design program for the 21^st century

by Donald C. Dilworth

The SYNOPSYS program has been under development for over 40 years, and is one of the largest and most powerful optics codes in the world. Some of the most important features are listed below; your attention is directed in particular to the AI, or artificial-intelligence capability, that lets you type an English sentence to define your own command or do nearly anything that you want. Sentences like "put the stop on 4", or "plot back focus for wavelength = .4 to .8", or "find the largest clear aperture". With its vocabulary of a few hundred words, this feature makes SYNOPSYS unique, powerful, and friendly.

Also of special interest is the SNAPshot feature that shows you the lens and its image during optimization. You can watch the lens change as the image improves.

The WorkSheet feature lets you change lens power, position, bending, or any other parameter in real time, by moving a slider with the mouse, while you watch the rays converge or diverge.

 

The Y-YBAR feature lets you define your lens by changing the first-order properties at any point in the system.

The rotating-perspective feature shows the lens on the screen, where you can easily view it from all angles by dragging with the mouse, even in true 3D with our red-blue anaglyph glasses.

 

 

 

SYNOPSYS Feature List

Systems: Refractive, reflective, centered, tilted, decentered, focal, afocal, accomodated afocal, sequential, non-sequential.

Coordinates: relative to previous surface, global to surface 1, local to previous surface (with Euler angles in any order), external coordinates, such as telescope pier. Output of lens and raytrace data in any coordinate system.

Object: Finite, infinite, Gaussian, Lambertian, Fast; polarized; Wide-angle, Constant object NA.

 This is an example of the MAP feature, where you can see the output polarization.  See the difference when you apply coatings to the  prism surfaces.

Capacity: 200 surfaces, 10 zooms, 1000 aberrations, 150 variables, 10 wavelengths, 6 configurations for simultaneous optimization.

Pupils: paraxial, real-ray, wide-angle (adjust at stop or at all surfaces), implied pupil via input ray aiming.

Surfaces: refractive, reflective, holographic, diffractive; coatings considered in raytrace.

Vendor catalogs: Melles Griot, Inc.; Spindler & Hoyer; Edmund Scientific Company; Newport Corporation; JML Direct Optics; CVI Laser Corporation; and Optics for Research, Inc. Match, insert, or replace a lens element with the click of your mouse with our complete list of 2960 stock lens elements.

Prism library: Right-angle, Amici, Porro, Penta, Dove, Schmidt, Pechan, Penta-roof, Double porro, Abbe. Insert or remove a prism with a single mouse click in the WorkSheet.
 

  Here is an example of an Amici prism. This uses a roof surface and nonsequential raytracing. It also gives the polarization shown above, if the roof is uncoated. But SYNOPSYS can model coatings too, and it will show the improvement in the polarization that results if the roof is aluminized. You can even design your own coatings with the built-in FILM program.

Shapes: Flat, sphere, conic section, power-series aspheric, biconic, biradial conic, toric, cylinder, non-rotationally symmetric asphere, perfect Fresnel, Fresnel with explicit zones, grating, holographic element, DOE, Zernike polynomial, linear & cubic spline.

Materials: Glass catalogs (Schott, Hoya, Ohara, Corning France, Guangming, LZOS, custom), IR & UV materials catalog, glass model, interpolation coefficients, exact indices, calculate coefficients to fit entered index data, wideband coefficients (12 terms), polarizing, birefringent, GRINs. On-screen glass table, graph of selected glass properties.  SYNOPSYS will compute the new index of refraction as you change the temperature or air pressure.
 

  This is a display of the Schott glass map, onscreen.  Select a glass type, and its properties can be instantly displayed, as shown below:

Apertures: Circular, elliptical, rectangular, decentered, inside, outside, polygon inside and outside, apodization, lens bevel, flat, etc.

System options: Vignetting check, adjust pupil to fill stop, adjust apertures to fit pupil, specify vignetting as a function of field point, real or paraxial CAO’s, adjust pupil size off axis, insert and remove surfaces, delete pickups, solves, tilts, decenters; fix & free clear apertures.

Pickups & Solves: Curvature, thickness (scaled + constant), index, tilts and decenters. Solves in both X and Y-directions.

Basic Analysis: First-order, third-order, fifth-order, paraxial raytrace, real raytrace, targetted raytrace, edge thickness, sag table, element weight, weight of lens, flux uniformity, illumination uniformity, narcissus, ghost image (real, paraxial, buried, plotted), ray fans, OPD fans, Gaussian beam trace, feathering point.

Here is an example of the ghost-image analysis feature. 

You can show these data in four different formats, including a perspective view of the lens with the paths of selected ghost rays shown.

Utilities: Lens store, get, save, fetch, reverse, scale, fold, unfold, HOE point definition, DOE exposure mask plot, curve fit to interferogram (power-series, Zernike polynomial), thermal soak, thermal shadow, toggle printer capture file, bell, MACro chaining, looping, save plot, get plot, truncate lens, concatenate two lenses, insert element from vendor catalog, recall last 20 commands.

 

  This is the exposure mask for a DOE at the 0.3 point of each fringe.

Pupil Wizard to define the entrance pupil; Spectrum Wizard to combine a source and detector spectrum, assign to lens; Edge Wizard to edit element edge geometry.

 

 

This is the Spectrum Wizard, combining a blackbody curve with the sensitivity of the eye.

Optimization: Variables: Radius, thickness, index, Nd, Vd, conic constant, tilts and decenters in local or global coordinates, aspheric coefficients, spline coordinates, object coordinates, HOE OPD coefficients, afocal accomodation, ZOOM position, GRIN parameters, HOE construction parameters; KICK the lens to escape from local minimum, simulated annealing for global optimization.   Can create and optimize a thermal shadow, where configuration 2 is the same as 1, with a termperature difference.

Alternate Configuration: 6 configurations, pickup curvature, thickness, index, tilts, decenters, HOE coefficients, object coordinates, all surface parameters.

Aberrations: Edge thickness limits, value; automatic ray generation (transverse aberration, OPD, wavefront variance, spot standard deviation); centroid location; OPD Zernike or power-series coefficient target, user-defined rays ((X,Y,Z) coordinates on any surface, (X,Y) distance from chief ray, OPD’s, radial intercept distance, diffraction MTF) ; first-order properties (focal length, back focus, total length, Gaussian image height, exit pupil position, paraxial defocus, object coordinates, F/number, afocal accomodation) ; section first-order properties (front focal length, back focal length, front focal distance, back focal distance, nodal point positions, separation, principal point positions, separation, entrance, exit pupil position, power in air) construction parameters (radius, thickness, index, dispersion, tilt, decenter, narcissus, reverse ghost reflection, aspheric coefficients, surface sag) ; Gaussian beam properties (beam radius, divergence, waist location, waist radius) , HOE point location in (X,Y,Z) third-order aberrations (spherical aberration, coma, astigmatism, Petzval curvature, distortion, primary and secondary axial and lateral color) ; third-order aberrations of selected portion of lens, fifth-order aberrations of lens or portion thereof; second-or fourth-power aberrations; "one-sided" aberrations, define an aberration via an equation; tolerance desensitization; Options: Derivative list, arithmetic combinations of aberrations, automatic testplate matching, summary of results, changes, final aberration contributions, graphics SNAPshot during optimization, DLS or PSD algorithm

Tolerancing: Inverse sensitivity of user-specified aberrations with respect to user-specified variables; automatic tolerance budget preparation based on wavefront variance, spot variance, Strehl ratio, diffraction MTF, boresite shift, magnification change, distortion change; at user-specified statistical confidence level; includes radii, testplate match, irregularity, thicknesses, index, dispersion, element wedge, element tilt, decenter; up to 4 adjustments. Monte-Carlo statistical verification of tolerance budget, with plotted histograms of simulated production runs.

Basic Graphical Analysis: Lens drawing, perspective drawing, rotating perspective drawing, solid model (optional shading), ray fans, OPD fans, field curves, distortion, element mechanical drawing, surface shape, departure from closest-fit sphere, drawing of all zoom positions, several lenses on one drawing, multiple kinds of analysis on a page.

Image Analysis -- Geometric: Footprint, moving-surface footprint, MTF, spot diagram, through-focus spot diagram, knife-edge trace, RMS focusing, RMS spot size, spot standard deviation, through-focus MTF; Image Tools for extended or point target, with or without aberrations.

 

  You can also get this analysis with diffraction images, plotted as visual images or as 3-D surfaces, like this:

Image Analysis -- Diffraction-based: MTF, through-focus MTF, multi-field MTF, pupil wavefront map, wavefront contours, wavefront fringes, point-spread function, wavefront aberration coefficients, wavefront variance, standard deviation, Strehl ratio, partial coherence analysis, image model, diffraction energy distribution; Image Tools for extended or point target, with or without aberrations..

 

 

Here is an exampole of the Graphical System Summary (GSS).  This analyis has many optional ways to display the results.

Image Analysis -- Image dissection: Encircled energy, slit trace, knife-edge trace, energy on detector of specified shape and position as a function of size or position. 

On the picture above you see  two surfaces: on the right is the diffraction point-spread function, and on the left is the MTF at that field point, plotted in 3-D.  See the slider bar under the diffraction pattern?  Drag it and both pictures rotate.  Look at either surface from any angle.

Image Analysis: extended source: Selection of targets: sine, square, three-bar, one-bar, knife-edge, slit, printed text; combine with geometric, diffraction, partial-coherent image.

 

  Here is how a sample of text would look imaged by a lens with aberrations, as shown by the Image Tools feature.  You can specify any target you want, selected from our menu -- or your own photograph -- to see the effect of lens aberrations and diffraction.

Want to see what an extended object looks like when imaged by your lens?

Process a photo with the Field Blur feature, and you get

Mapping function: Map of projected ray angles or incident angles, footprint, X, Y, or Z-coordinates, SAG, HOE frequency, grating frequency, spot diagram, distortion, OPD’s, pupil shape, transmission, polarization; over field of view or over pupil; plotted or printed output; digital or analog format; map of differences between two maps.

This plot shows the wavefront hitting a surface following a pinhole where the beam is diffracted.

Diffractive Propagation:  Examine the intensity profile of a Gaussian beam anywhere in the system, or the effect of a pinhole at an intermediate image.  Plot the phase of the fringes in a diffraction pattern.

Design the lens cell with SYNOPSYS.  Then make drawings of all of the parts, with dimensions.

Engineering options: Model of surfaces or indices displaced at nodes calculated from thermal or structural programs (such as NASTRAN).

Interactive Features: HELP files (online Tutorial and User's Manual), "Instant HELP", MACro full-screen editor, graphics display, hardcopy output, "SketchPAD" program (split-screen display of lens and image: lens Y-Z profile, perspective drawing, paraxial profile, ray fans, OPD fans, spot diagrams, astigmatic field curves) "WorkSheet" program (edit lens data on screen, pictures update; move sliders to alter curvature, spacing, bending, or slide element; insert and remove surfaces and elements, flip element, split element with airspace or buried surface), programmable toolbar buttons to perform most common tasks instantly, adjust font size onscreen, adjust pen width for plots, dialog windows to perform most optimization and analysis tasks. Spreadsheet dialog for editing most system and surface parameters. Arrow keys to recall last 20 commands.

Artifical Intelligence Features: Natural-language input for altering and retrieving lens parameters, automatic starting-point calculation based on lens data file, lens alteration based on comparison of aberrations with correction obtained in lens data file. Graph of almost anything vs. anything as any lens parameter is varied; symbol-substitution feature to define custom commands. Can search vendor catalogs to find closest match to a given lens.

Here is an example of what the AI feature can do.  We typed the English sentence "Plot back focus for wavelength = .4 to .8"  This is the result:

The above examples give you a taste of the enormous feature set of this state-of-the-art lens design and analysis package.  There is much more to see.  Download SYNOPSYS today, and when you run it the first time, it goes automatically to the Help File, where you can select the Tutorial Manual.  There you will work some simple examples and become familiar with the program.  Then look at the Table of Contents of the User's Manual.  Prepare to be impressed.